Lock nut



o. seen-r 2,379,794 w July 1945.

v LOOK NUT Filed Jan. 29. 1945 Patented July 3, 1945 UNITED STATES PATENT orrlcs Application January 29, 1943, Serial No. 473,995 In Great Britain January 27, 1942 Claims. (Cl. 151-20) This invention relates to lock nuts and has for its oblect 'to' provide an improved nut which avoids or reduces the necessity for loci: nuts or spring washers or other locking-devices,-especially in cases wherethe nut is subjected to vibration and possibly severe vibration;

The inventionin brief consists in a nut formed in or into a condition where it has a certain amount of twist resulting in relative movement in a longitudinal direction, which twist is wholly or in part taken up or employed to exert a pressure, for instance on co-operating threads or a co-operating surface on the nut being tightened.

Theinvention also consists in=nuts in accordance with the preceding paragraph formed with a longitudinal or other cut whether straight or curved or place of weakness in the side wall of. the nut whether a, face or an angle, in conjunction with which one or both'of the end faces of the nut is formed at an angle-to the longitudinal axis for instance, as a surface of a helix or is stepped. a

The invention also consists in a form of nut according t0 the preceding paragraph in which the modification of the end of the nut is replaced by a washer having a modified face, for instance,

formed as a helical surface.

The invention also consists in improved nuts substantially as hereinafter described with reference to the accompanying drawing.

In a modified form illustrated in Figure 4 the slot 0. is inclined to the axis of the nut.

In the case of an inclined slot or curved slot;

the width of the slot should be sufllcient to per- 1 mit of the necessary degree of twist to b obtained.

Instead of the nut being entirely cut through by a-longitudinal slot or the like the slot may be only partially cut through, leaving a bridge, but

in order to give suflicient resiliency or twisting capacity the slot should extend through the wall I of the nut "otherwise than in the region of this bridge. I

An example of such a construction is illustrated in Figure 5 in which abridge c is left at the centre of the cut a. h

If desired a ring for strengthening may be applied around the nut to prevent the slot being too widely opened on tightening the nut, an example of such arrangement being illustrated in Figure 6. The' depth a: of the ring 1 should be less than minimum height of the circular'boss 7'.

Referring to the accompanying diagrammatic drawing Figure 1 is an elevational view of one convenlent construction of nut embodying the present invention.

Figure 2 is a plan view thereof.

Figure 3 is a cross-sectional view onthe line A-A thereof. v

Figures 4, 5 and-6 are-isometric views of fur ther modified constructions.

In carrying the invention intdeifect in one a form illustrated by way of example in Figures 1-3, I take a standard nut, cut a small slot (1 longitudinally completely through the side wall and modify the shape of the base b of the nut so that instead of it being a plane surface it is in the- It is not essential that the lower face of the nut should be provided with a helical surface but some modification of a plane surface could be made so that in eflect-the parts of the base ad- Jacent the slot are of somewhat diflerentheight.

The slot need not be. at right angles to the base,

e. g. as injlgures 1-3 5 and 6, but may be inclined, e. g. asin Figure 4, or curved. Both ends of the nutmay be modified instead of only one end but in all cases a normally thr'eaded boreis employed and the structure of the finished nut is normal, that is to say, unbent. I

- I claim: v

1. A nut comprising a body having a threaded bore and beingslotted inwardly through one face whereby adjacent portions of the body may be relatively displaced in the direction of the axis gaging end of said body for effecting relative disof the bore, and step like means at the object enplacement of said portions as the body is advanced against an object along the threadldf a bolt and thereby cause the body thread tojfirmly grip the bolt thread. l

2. A nut as claimed in claim 1, means for effecting displacement is constituted by a stepped formation of the object engaging face of the body.

3. A nut as claimed in claim 1, wherein said means for effecting relativedisplacementfis constituted by a helical configurationof the object engaging face of the body. 1

4. A nut as claimed in claim 1, characterized by the provision of a ring surrounding thebody wherein said arranged to prevent expansion of the body but permit relative displacement of said portions.

5. A nut comprising a body having a threaded bore and slots extending partially through the body from the opposite races thereof to weaken said body whereby adJacent portions thereof may be relatively displaced in the direction oi. the axis of the bore, and means for eflectln: relative displacement or said portion: as the body is advenced against an object alcn: the thread or a bolt and thereby cause the body thread to firmly 5 grlp the bolt thread.

o'rro EGER'I'. 

